Saline infusion sonography (SIS), also known as hysterosonography or sonohysterography, is a minimally invasive ultrasound (US) technique that involves infusion of a small volume of sterile saline into the uterine cavity. It acts as a negative contrast medium that delineates hyperechogenic endometrial lining. Contrast enhanced sonographic studies provide high-resolution images of the uterine cavity enabling detection of focal and diffuse intrauterine abnormalities. In addition to visualizing intrauterine lesions, such as endometrial polyps, fibroids, and adhesions, it can assist in differentiating between different types of congenital uterine anomalies. The objective of our article is to assess the diagnostic value, indications, contraindications, and possible complications of SIS. Various clinical scenarios and typical appearances of intrauterine, endometrial, and subendometrial lesions detected by SIS are illustrated and compared with hysteroscopy images and/or macroscopically similar surgical pathology specimens. The literature on SIS is reviewed and authors discuss case-specific pitfalls and technical challenges that may lead to patient discomfort, poor image acquisition, incomplete assessment, and wrong interpretation of the images.